The present invention relates to a semiconductor integrated circuit device having an overheating protector for protecting a semiconductor integrated circuit on a semiconductor integrated circuit board against overheating, and a method of protecting a semiconductor integrated circuit against overheating.
Chips of semiconductor integrated circuits, such as LSI circuits or the like, are greatly heated when the circuits operate at higher speeds. In certain applications, the chip is heated to such a high temperature that it may possibly be destroyed due to its own heat.
Generally, the heating of a semiconductor integrated circuit is closely related to the amount of electric energy consumed thereby so that the greater the electric energy it consumes, the larger the amount of heat it generates. Semiconductor integrated circuits are roughly classified into bipolar and C-MOS types. Recent years have found widespread use of C-MOS semiconductor integrated circuits which have a smaller power requirement when not in operation. The amount of electric energy consumed by C-MOS semiconductor integrated circuits is proportional to the operating frequency thereof. Therefore, the higher the operating frequency of a C-MOS semiconductor integrated circuit, the larger the amount of electric energy consumed thereby. As shown in FIG. 5 of the accompanying drawings, the amount of heat generated by the C-MOS semiconductor integrated circuit increases in proportion to the operating frequency thereof.
Personal computers or other electronic products that incorporate semiconductor integrated circuits which can be heated to high temperatures are normally equipped with a cooling system such as a cooling fan or the like for protecting the semiconductor integrated circuits and other parts against overheating. When the cooling system suffers a failure, a warning is issued to prompt the user to take a certain preventive measure for protecting the semiconductor integrated circuits and other parts against overheating.
Electronic apparatus such as video game machines for business use also incorporate various semiconductor integrated circuits and are usually installed in such environments which prohibit them from being directly manually accessed for overheat protection while in operation. Even if the cooling system of such an electronic apparatus fails, such a failure will usually remain undetected until the electronic apparatus itself suffers a failure or operates uncontrollably.